Item No.: CO4205-1J

UniTrain: Battery Disconnect Unit in Hybrid and all Electric Vehicles

High-voltage battery disconnect unit (BDU)

The battery disconnect unit training system allows the design and operating principle for disconnecting a high-voltage battery from the on-board network to be investigated.


  • Experiment card with circuitry for experiments in Eurocard format
  • Labsoft browser, course software and additional virtual instruments
  • Storage case
  • Jumpers

Components on experiment card:

  • Electronic circuit for battery disconnect unit (BDU)
  • Measuring sockets
  • Fault simulation circuitry
  • Two battery blocks
  • Three relays
  • Microcontroller-based control
  • Service and maintenance plug
  • Ignition switch
  • Lamp to indicate when ignition is on
  • High-voltage fault switch
  • High-voltage fault indicator
  • Pilot disconnecting bridge
  • DC-link circuit capacitor
  • Load for on-board network
  • Display of on-board network load
  • Measurement sockets for battery blocks
  • Measurement sockets for on-board network

Training contents

  • Fundamentals of battery disconnect units
  • Compiling repair shop orders
  • Diagnostic functions
    • Reading out fault memory with a diagnostic tester
    • Classifying faults in vehicle systems
  • Function and design of a pilot line
    • Design of electric circuit
    • Principle of operation
    • Control
    • Circuit variants
  • Repair methods and conversations with customers
    • Selection of repair actions as specified by manufacturers
    • Working with spare part numbers
  • Investigation using measuring instruments
  • Effect of faults commonly seen in practice (simulated faults can be activated)
  • Course duration 7 hours approx.​​


  • 100 x 170 mm (width x height)
  • 0.8 kg